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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
Wayne A. Houlberg, Robert W. Conn
Nuclear Science and Engineering | Volume 64 | Number 1 | September 1977 | Pages 141-150
Technical Paper | doi.org/10.13182/NSE77-A27085
Articles are hosted by Taylor and Francis Online.
Research on the development of numerical techniques to simulate the space-time evolution of large tokamak plasmas is reported. A nonuniform spatial mesh technique is employed to allow more accurate calculations in the boundary of reactor-size plasmas. A box integration method is used to maintain the accuracy of central differencing on the nonuniform spatial mesh and to preserve both the particle and energy flux. A variable implicit technique is used for the time expansion. The time-centered (Crank-Nicholson) technique used in most other models generally offers greater accuracy but can lead to severe limitations on the time step. Somewhat more implicit treatments can remove the numerical limitations on the time step without seriously affecting accuracy. The physical time scales, which can change by several orders of magnitude from startup to equilibrium, can then be used to continually adjust the time step throughout a calculation. Sample calculations are presented for a near-term tokamak engineering test reactor and a conceptual tokamak power reactor, UWMAK-III.